Disorder (GCMP)David M. WhisnantDisorder: this is a resource in the collection "General Chemistry Multimedia Problems". A spontaneous change is one that has a natural tendency to occur without needing to be driven by an external influence. This problem will explore the influence of entropy, a measure of disorder, on the spontaneity of a few processes. General Chemistry Multimedia Problems ask students questions about experiments they see presented using videos and images. The questions asked apply concepts from different parts of an introductory course, encouraging students to decompartmentalize the material.

Thermodynamics

Two Solids (GCMP)David M. WhisnantTwo Solids: this is a resource in the collection "General Chemistry Multimedia Problems". When two solids barium hydroxide octahydrate, Ba(OH)2. 8H2O and ammonium thiocyanate, NH4SCN are mixed, they react. We will explore the thermodynamics of the reaction. General Chemistry Multimedia Problems ask students questions about experiments they see presented using videos and images. The questions asked apply concepts from different parts of an introductory course, encouraging students to decompartmentalize the material.

Thermodynamics

Gas Phase AcidityThis site provides a very comprehensive collection of thermodynamic data selected by the scientists at the National Institute of Standards and Technology (NIST).

Thermodynamics

A Lattice Energy SpreadsheetChristopher KingA Lattice Energy Spreadsheet is a tool that easily calculates lattice energies. It also illustrates the relation between crystal structure, coordination number, and ionic radii. A Lattice Energy Spreadsheet contains five related worksheets: Lattice Energy, MX Structure Map, Kapustinsky Lattice Energy, Directions, and Discussion, each described below. In the Lattice Energy worksheet, the lattice energy of many binary compounds can be calculated in about a dozen mouse clicks. An element is selected, and the radius corresponding to the desired charge and coordination number is selected. The same is done for the counter ion, and the anticipated crystal structure of the compound is chosen (rock salt, wurtzite, etc.). The lattice energy is then calculated. This sheet uses enthalpies of formation of monatomic gaseous atoms from the elements, ΔH°form, to calculate lattice energies. The results are more accurate than the values obtained by simply summing enthalpies of fusion and vaporization. The results of the corresponding Born-Haber cycle are also graphed on this sheet.

Thermodynamics

A Pedagogical Simulation of Maxwell's Demon ParadoxD. López, C. CriadoMaxwell's demon was conceived by James Clerk Maxwell in 1871 to illustrate the statistical basis of thermodynamics (1), and the concept has since formed an arena for investigation and clarification of many concepts in thermodynamics (2). Chemistry students often have difficulty developing an intuitive knowledge of some concepts in thermodynamics. A Pedagogical Simulation of Maxwell's Demon aims to help make these concepts more understandable for students. Teaching thermodynamics from the microscopic point of view can help students develop an intuitive understanding of its concepts. This program simulates, at the microscopic level, two gas chambers with an opening between them. The program allows students or their instructors to set up simulations that illustrate the thermodynamics and statistical behavior of the system. The user determines the basis for whether the demon permits or denies passage of particles through the opening using information from the microscopic level, such as specific particle velocity. Students can track and analyze how this affects particle distribution, thermal equilibrium, relaxation time, diffusion, and distribution of particle velocities.

Contrail. A Module from the Physical Chemistry On-Line ProjectFranklin M. C. ChenThe condensation trail, or contrail, that trails behind a jet plane is an everyday observable phenomenon. These manmade cirrus clouds can persist for hours, or even days and can spread over thousands of square kilometers. This is a concern because clouds are major variables that control Earth's atmospheric temperature and climate. Understanding the impact of contrails on Earth's climate is an active area of research. Further, contrail formation can be examined in terms of the operative thermodynamic phenomena. The process of contrail formation involves combustion, cooling, and ice formation, all common topics in the undergraduate physical chemistry curriculum. The project when it is subdivided into separate manageable subjects is a good, comprehensive exercise for physical chemistry students.

The Reaction Rolodex; A Web-Based System for Learning Reactions in Organic ChemistryEric MahanThis Web-based system of note cards has been developed to aid students in learning the vast number of reactions encountered in organic chemistry. A thorough knowledge of these reactions is essential for success in first- and second-semester organic chemistry courses. The reactions are organized by functional group and can be chosen from a menu at the left side of the Web page. Once a particular reaction has been selected, the main frame displays the reactant(s) and reagent(s) along with a question mark in place of the product. After considering the reaction as long as needed, the user can click the question mark to reveal the reaction product. Clicking the product will again hide the answer and regenerate the question mark so that the reaction can be practiced again. Selecting other reactions from the menu on the left allows them to be practiced in the same manner.

The Relation of Temperature to Energy SpreadsheetChristopher KingThe relation between temperature, energy, and the properties of a material is well developed. While this relation is not clearly elaborated in most physical chemistry textbooks, these relationships can easily be included in the early part of a physical chemistry course on thermodynamics, and this interactive Excel spreadsheet can help.

JavaScript Programs To Calculate Thermodynamic Properties Using Cubic Equations of StatePatrick J. BarrieCubic equations of state are widely used by chemists and chemical engineers to predict the thermodynamic properties of both pure substances and mixtures. In particular, these equations enable predictions concerning the temperature and pressure at which vapor liquid equilibrium occurs. These two educational JavaScript programs perform calculations using cubic equations of state and, equally importantly, explain how the calculations are performed.

Mathematics / Symbolic Mathematics |

Chemometrics |

Thermodynamics |

Equilibrium |

Enrichment / Review Materials

3D Molecular Symmetry Shockwave; A Web Application for Interactive VisualizationNickolas D. Charistos, Constantinos A. Tsipis, Michail P. Sigalas3D Molecular Symmetry Shockwave is a Web-based application for interactive visualization and three-dimensional perception of molecular symmetry. The user interface is simple, and students learn how to use the program from the built-in help screens. The animation uses the Macromedia Shockwave browser plug-in, and requires a download of only 256 KB, allowing it to be used even with low bandwidth Internet connections. Its performance is comparable to a desktop application.

Crystals / Crystallography |

Group Theory / Symmetry |

Molecular Properties / Structure |

Thermodynamics

Computer Simulations of Salt SolubilityVictor M. S. Gil, João C. M. PaivaComputer Simulations of Salt Solubility provides an animated, visual interpretation of the different solubilities of related salts based on simple entropy changes associated with dissolution: configurational disorder and thermal disorder. This animation can also help improve students conceptual understanding of chemical equilibrium before any quantitative interpretation of equilibrium constants is attempted.

Computational Chemistry |

Solutions / Solvents |

Thermodynamics |

Equilibrium |

Precipitation / Solubility

An Animated Interactive Overview of Molecular SymmetryMarion E. Cass, Henry S. Rzepa, David R. Rzepa, Charlotte K. WilliamsAn Animated Interactive Overview of Molecular Symmetry is a series of Web pages designed to help instructors teach molecular symmetry. These pages combine interactive Jmol images and instructional text that allow students to examine and explore the operations and elements that give rise to molecular symmetry.

Named ReactionsMichael B. SmithThis Web site lists 95 of the most important named reactions in organic chemistry. Each is linked to a Web page that gives the primary reference and equations for one or more recent literature examples that illustrate the use of the reaction.

Nomenclature / Units / Symbols |

Reactions

Named ReagentsHans J. ReichThis convenient list provides structures of more than 160 common reagents used in organic chemistry that are often referred to by the originator's name, by an acronym, or by a trade name.

General Chemistry Multimedia ProblemsDavid M. WhisnantGeneral Chemistry Multimedia Problems ask students questions about experiments they see presented using videos and images. The questions asked apply concepts from different parts of an introductory course, encouraging students to decompartmentalize the material.

Chemical & Physical ChangeAmerican Chemical SocietyEverything you see and touch has the ability to change. Sometimes substances change to form new substances. This is called a chemical change. Other times substances change but keep the same identity. This is called a physical change. Try these activities to learn more about chemical and physical change.

Characteristics of MaterialsAmerican Chemical SocietyWhat makes diapers absorbent? Is peanut butter stickier than syrup or jelly? Strong, stretchy, sticky, or sweet—everything around us has special properties which make them unique. See if you can identify and compare the characteristics of materials.